Google Widens Its Lead Over Yahoo

Search engine marketing firm Didit sent us this chart measuring their clients' spending on Google (GOOG) versus Yahoo (YHOO) since Q4 2004. Didit's clients are 95% in the U.S., 5% international. Excepting a slight reversal last quarter -- due to "an unusual strategy we employed for one very high-spending client" -- the chart shows that the gap between the two only continues to widen.

Microsoft (MSFT) CEO Steve Ballmer would say that because more search ad buyers would be bidding for the same keywords, the Yahoo line would start to trend upward if the company combined its search business with Microsoft's.